6 replies to this topic

[johnv]

998 1968 Cooper .. the car is not overheating, but water is disappearing. After a bit of google I think the radiator cap maybe the problem .. the radiator neck is an inch from the lip to the shoulder, and the cap is slightly less than 3/4 from the seal to where the cap sits on the lip .. so basically it can't be sealing at all!

I can't see anything on the minispares site which would give me a cap with a longer reach .. any suggestions? thanks

 

correction .. there is one http://www.minispare...|Back to search

 

but only rated at 8lbs ...

 

more accurate measurements would indicate that I have a 3mm gap between the seal and the shoulder

Edited by johnv, 10 June 2019 - 08:16 AM.

[Haynes]

Try putting rad overflow hose into a little container and see if its blowing water out.


The earlier rads do have longer neck but only lower pressure cap available, dont think you can get 15lb option.

Had this on a couple of engines recently, if it's not the cap, afraid so say its most likely the head gasket. When our head was skimmed they found it was definitely warped.

[johnv]

Try putting rad overflow hose into a little container and see if its blowing water out.


The earlier rads do have longer neck but only lower pressure cap available, dont think you can get 15lb option.

Had this on a couple of engines recently, if it's not the cap, afraid so say its most likely the head gasket. When our head was skimmed they found it was definitely warped.

 

I'm pretty sure it's that cap .. there's no pressure all due to no seal (3mm gap between seal and shoulder) .. I'll put the low pressure one on

[cal844]

Could also be needing a very good flush dur to back pressure at a blockage

[phillrulz]

+1 for putting the overflow hose into a bottle and taking it for a drive. Bare in mind the first drive it may expell some water so it can find the right level if you over filled 

[gazza82]

If there is a 3mm gap then it's being blown straight out the overflow as soon as it starts to get hot ..

[johnv]

If there is a 3mm gap then it's being blown straight out the overflow as soon as it starts to get hot ..

 

yes, that's my thinking!